1. Field of the Invention
This invention relates in general to improvements in the field of computer systems having backup/restore or archive/retrieve subsystems, and more particularly, to host storage management of Outboard Data Movement (ODM).
2. Description of Related Art
Data processing systems are required to store large amounts of data. As data processing systems become more complex, the management, control, and movement of the data required by the system, becomes a larger task for the processor.
Typically, the host processor of a system controls and manages the data through paths that travel through the host processor. This process involves the management of data, as well as requiring the Central Processing Unit (CPU) of the system to spend a significant portion of time manipulating data when the CPU could be performing other tasks.
Further, many systems contain multiple data storage subsystems, e.g., backup/restore subsystems that are typically used to save a recent copy or version of a file or portion thereof on some form of backup data storage device, such as magnetic or optical disk drives, tape drives, or other memory, multiple Direct Access Storage Devices (DASDs) for storage of large amounts of data, etc. The constant management of multiple storage devices is a further drain on CPU processing time. Those engaged in the field of data processing and especially in the field of data storage subsystems are continuously striving to find improved methods and systems to reduce the demands of backup/restore subsystems. Further, present systems are reaching their scalability limits and can no longer use parallel processing to manage the amounts of data required in the time allotted for these tasks.
However, some host processor involvement is still needed to maintain several qualities of the data, e.g., the "current" copy of the data, data security, the data format, and the consistency of the data for a given application.
It can be seen, then that there is a need for a method of managing data that reduces host processor involvement. It can also be seen, then, that there is a need for a method of managing data that allows the data to be controlled in a more efficient manner. It can also be seen, then, that there is a need for a method of managing data that retains host processor involvement for certain data qualities.